Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuinely non-structured context: client-dependent rendering (interactive card in Claude/ChatGPT vs JSON elsewhere) and an entitlement prerequisite ('Requires Pro plan or higher'), both of which affect how an agent should invoke and present the result.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences, front-loaded with the data payload and followed by rendering and entitlement notes. Every sentence carries distinct information, though the card-rendering clause is only marginally relevant to tool selection.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return-value explanation is not required, and the description covers scope (this month), delivery format, and the plan prerequisite. The only remaining gap is the absence of routing guidance relative to sibling aggregation tools.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool takes zero parameters, so there is nothing for the description to disambiguate. Baseline for a parameterless tool is 4; the description adds the useful note that scope is fixed to the current month.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names a specific resource ('this month's program snapshot') and enumerates the exact contents (revenue, conversions, commissions, top affiliates, recent conversions), so an agent knows precisely what comes back. It does not, however, contrast itself with close siblings like get_stats or list_conversions, so differentiation is left to inference.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

'in one call' implicitly signals this as a consolidated alternative to several separate calls, which is useful, but the description never explicitly says when to prefer it over get_stats or list_conversions. Usage is implied rather than stated.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.